The present invention relates to a communication method using a small scale computer network and a communication equipment used therefor. particularly, the present invention is concerned with a communication method and an equipment therefor capable of accumulating a plurality of communication data (which will be called "frames" hereinafter) at the same time to optionally change the transmission interval between frames when they are transmitted to the network in sequence, thereby eliminating the possibility that only a specified communication station occupies the network.
For one of communication systems to construct LAN (Local Area Network) which is the small scale computer network, there is known CSMA/CD (Carrier Sense Multiple Access with Collision Detection) system. According to this system, a single coaxial cable is used as a transmission medium and all communication equipment are connected in parallel with the medium. A judgement as to whether transmission signals by other communication equipment are present or not on the medium is made. Only when such transmission signals are absent, transmission is enabled, and when it is recognized that other communication equipment except for the self-station or self-equipment effect transmission substantially at the same time, transmission is interrupted to make a judgement for a second time as to whether the above-mentioned transmission signals are present or absent.
There is a tendency that communication equipment for realizing such a communication system is constituted with an LSI dedicated thereto. The feature of such an LSI resides in that the LSI has a function to input a plurality of data related to frames to be transmitted in advance as control data thereby to transmit frames in succession.
However, when the LSI has such a function, the communication equipment operates so as to transmit frames at minimum time intervals. Accordingly, frames will be transmitted one after another on the network medium every minimum interframe time (which will be called "IFS (Interframe Spacing) time" hereinafter).
On the other hand, when there is a frame to be transmitted in other communication equipment on the network, this communication equipment also initiates transmission of the self-frame when the IFS time has elapsed after the frame disappears on the network. In this instance, two communication equipments will effect transmission of frames substantially at the same time. As a result, these frames collide with each other and the contents thereof are broken. Thus, it is necessary to again restart the transmission procedure from the stage of the carrier sense, giving rise to the problem that efficiency in use of the network is extremely low.